A conventional one-dimensional (1D) ultrasound probe comprises a line of transducer elements from which ultrasonic signals may be emitted. Furthermore, an image plane underneath the transducer elements may be observed by detecting echoes of reflected ultrasonic signals coming from inhomogeneities of the observed region. By correctly positioning and moving the ultrasound transducer, a volume of interest of the subject comprising for example a lesion may be observed.
In ultrasound imaging of a volume of interest, a clinical challenge for doctors—especially junior doctors—is how to find an imaging plane for the volume of interest which is suitable or desirable for a certain clinical purpose. Supporting doctors to find the desired imaging plane is very valuable and highly required for clinical doctors. From the point of view of computerized techniques, the 2D image data acquired by the one-dimensional ultrasound probe may not provide sufficient information to do this, since the human body is a 3D object. Currently, the research work done for this goal is mainly based on 3D (acquired by using a matrix transducer comprising a two-dimensional array of transducer elements) or higher-dimensional data and once the high-dimensional data is obtained, the desired imaging plane with the object that doctors want to see may be determined and the corresponding 2D image of the desired imaging plane is displayed.
As regards the two-dimensional matrix ultrasound transducer, such a transducer may comprise an array of ultrasound transducer elements arranged in columns and rows. The transducer array face may still be rectangular as in the case of a one-dimensional ultrasound transducer, but the array of transducer elements is arranged in a two-dimensional matrix. This additional complexity may allow ultrasound beams to be steered and focused through a three-dimensional space rather than in only a plane. As is known to those skilled in the art, the two-dimensional matrix ultrasound transducer may acquire the three-dimensional volume data of the volume of interest from ultrasound echo data of a plurality of scanning planes in the volume of interest. The plurality of scanning planes may be determined by the setting parameters for the transducer elements, for example, which lines or rows are to be enabled, and the beam-forming parameters for the enabled elements.
Once the three-dimensional volume data of the volume of interest is acquired, any desired image plane can be reconstructed via computer processing algorithms, for example, by interpolation of the ultrasound echo data of the plurality of scanning planes.
Nevertheless, although it may be easier for doctors to find the desired imaging plane for the volume of interest with a two-dimensional matrix ultrasound transducer, the quality of the reconstructed and displayed 2D image of the desired imaging plane may be unsatisfactory.
Specifically, current automated means to reconstruct the 2D image of the desired imaging plane have some disadvantages, for example fixed enablement of the transmit elements of the matrix transducer regardless of the desirable imaging plane, etc. In other words, the image of the determined desired imaging plane may not be constructed in the transmit direction of the ultrasound signal. Since the ultrasound signal will have a signal focusing process and the corresponding interpolation process, if the image of the desired imaging plane is not generated in the transmit direction (i.e., not generated by the ultrasound echo data of the desired imaging plane itself) but reconstructed by interpolation of the ultrasound echo data of the plurality of scanning planes in the volume of interest, the quality of the constructed 2D image may be highly affected and sometimes clinical diagnosis cannot be performed for some applications where a high data quality is required.